Water-heater.



F. W. ROBERTSHAW.

WATER HEATER.

APPLIOATION FILED MAY 12, 1911.

1,097,265, Patented May 19, 1914.

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e f Q I i v i 1 1 1 a Q E1 a g 8 CIIIIIIIEIL- .(D R N Y e W N r me p q f a 6 l q v .1 1 Q WITNESSES V INVENTOFI nnrrnn STATES PATENT OFFICE.

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a I Specification of letters iatent. hppllca'tion filed May 12,- 191-1. Serial 1%. 626,882.

Patented Ma 19, 1914.

To all whom it may concern:

Be it known'that I, Fnnonnron W. Ronnn'rsHAw, 'of Pittsburgh, Allegheny county,

. nec'tions, and-the diaphragm valve and its connections. I I

My invention has relation to water heaters, and more particularly to gas fired heaters havin a heating element in which the water is eated and which is connected with a storage drum or reservoir.

My invention relates especially to improved valve mechanism :lor controlling the gas through the agency'of a themnostatlc device; and is designed to provide means of this character by which the gas iseither fully turned on or is entirel shut oil (with the exception of a small pilot light) in a substantially instantaneous manner.

A further object of my invention is to provide means for taking care of any leakage of gas which may occurin a manner to prevent waste and interference with the propel-operation of the burner The objects and advantages of my invention will more fully hereinafter appear.

' In the drawings, the numeral 2 designates the casing of a heater having therein a lieatin coil 3 of -any approvedform, and

which is connectedat its lower end by a pipe 4 with the lower portion of a reservoir or .drum 5. The upperendof the coil is concoilB, and for also nected bya pipe 6 tothe upper portion of the drum or.reservoir. -f

7 designates a gas "supply pipe for supplying the burner 8 underneath the heating supplying the pilot light orburnerlh i 1O is' the casingof a diaphragm-valve, which is interposed in the gas supply pipe 7 between the cut-oil valve 7 and the mixer llicj'i the burner 8. Theldiaphragm casing 10'Qis formed in upper and lower sections suitably secured together the lower section having a connection 12 for the inlet portion of the pipe 7 and also a connection 13 for the outlet portion of the pipe 7 leading. to.

valve-seating flange 15.

the burner; The two sections of the casing inclose the diaphragm chamber 14, into which the connection 121le'ads, the opening into said chamber being surrounded by a 1e desi ates a flexible diaphragm, which is secure at its edges between the two sections of the casing 10, and which divides the chamber 14 into two compartments. Attached to the underside of this diaphragm by means of a hollow screw 17 and clampingnuts 18, is a valve disk 19, which is arranged to seat upon the ring or flange 15.:

The screw 17 has a small aperture 20 in its upper end. The upper section of the diaphragm casing has a central depending ange or cup 21, whose lower edge is a short distance above the diaphragm and against which the diaphragm is arranged tofseat when raised. .-This cup or flange provided with a small perforation 22. The upper section of the diaphragm. section is arranged ,with a connection 23 to receive a pipe 23 leading to a thermostatically operated valve The valve 2i may be of vaform substantially as shown and described in my Patent No. 998,262 dated July 18,1911.

25 is a movable valve member, which controls the flow of stem 26 is actuate by the thermostatic element 27. This thermostatic element is shown s and whose adjustable as extending upwardly into the lower por-- tion of the drum or reservoir 5, the valve .rious forms, that illustrated being of thelower portion of the diaphragm casing and having a regulating valve 9.

The operation is as follows --The thermostatic valve 25 is rovid'ed with a s ring spring-acting in opposition to the thermo-' 25" which tends to ho dthe valve close this stat element 27, and being adjusted so as to be'overcome by the action of said element when the desired temperatureofwater is the-burner 8 is in operation, the s flows through theconnection 12-111mm lower compartment of the dia hragm chamber 14,

and by its pressure on t e under side ofthe .valve disk 19 lifts said disk sufliciently to obtained in the drum or reservoir 5. When 22, this escaping as will pass into the pipe ring or flange and thence tothe burner. A small quantity of the gas will escape through the opening of the hollow screw, and the dia hr'agm being pressed upwardly against the ower edge of the coupler flange has been escaping through the apertures 22 and 23 can'no longer flow past the'valve25. When this takes place, the *gas will accumulate in the upper compartment of the diaphragm chamber, until a pressure is created in such compartment sufficient to overcome the pressure below the diaphragm, and to close the valve disk 19 against itswseat 15. The flow of gas to the burner 8 is then immediately cut oif and remains cut ofi until the temperature of the water in the drum. or reservoir 5 falls below the given temperature and causes the thermostatic element toagain open the valve 25. The opening of the valve 25 relieves the accumulation of pressure in the upper compartment of the diaphragm chamber, and enables the valve 19 to open and a full flow of gas again passed to the burner 8. The opening through the valve 19 is of a large area compared to the pipe area leading to the burner, so that the action of said valve is practically instantaneous, and the gas at the burner will either be turned on in full, or closed off completely. The area of the valve opening 25 is also large compared to the area of the escape openings 22 and 23, so that the action of this valve is also practically instantaneous.

An important feature of my invention consists in the fact that the valve mechanism described operates to give either a full flow of gas at the burner 8, or entirely shuts ofl such flow.. This is desirable for a number of reasons. In all heating systems where the heating is done in one member, and the heated material is thenpassed to another member, the time required is sufliclent to maintain, in an ordinary arranged boiler, hot water of difl'erent' temperatures, running as much as thirty. degrees in a boiler five feet long and standing upright, as usually placed. The hot water is always drawn from the top of the boiler; and if the water at this port on of the boiler is at a temperature' of say one hundred and forty degrees and the thermostat-which extends into the lower portion of the boiler is set to act at one hundred and-ten degrees, the valve 25,

as soon as it closes, shuts off the escapement flow of gas to the burner 9, and 'the flame water in the boiler, however, gradually works down, and the colder water at the lower part where the thermostat is placed surely but slowly absorbs the heat in the hot portion, keeping the water above the thermostat slightly above its regulation, and insuring a closed valve, until the temperature of practically-all of the water in the boiler falls below one hundred and ten degrees. Unless the boiler and heater are in a very exposed place, if no water is drawn from the boiler, the valve will remain closed for a number-of hours. As there is no circulation from the heating element to the boiler and back, there is no chilling of the water by passin through the cold heater as would occur id not the air currents or drafts substantially cease as soon as the gas" ceases burning. Although the pilot light is still kept burning, the amount ofas consumed by it is very small, and even t is small amount is not wasted, as the greater part of the heat from it is absorbed by the heating member or coil. thereby reduced to a minlmum, overheat ng is prevented, and the retarding circulation feature above described is taken advantage of to the benefit of the device and to the accomplishment of one of the main purposes of the invention, namely, economic gas con sumption. Furthermore the practically instantaneous opening and closing of the gas supply port to the main burner, effectively prevents all danger of flashing back of the lighted gas in the mixer or Bunsen burner, which is extremely dangerous both to health and to the surroundings. The present tendency in manufacturing is to increase the heating capacity of burners without increasing their size, and this is usually done by increasing the size of the holes in the burners. This makes the burners still more liable to flash, and the only safe remedy is to have the burner burn only at its greatest consuming point, doing its heating quickly, and then shut ofi'. quickly until such time as the temperature is reduced, when the gas comes on again as quickly as it was shut off. This cutting off andturning on of-the gas is effected by my invention too rapidly to permit flashing. I

The returning of the escaping gas to the pilot light, not only prevents waste of fuel, but has a number of advantages over returning it into the main burner. In the first place, it insures the consumption of the gas in case any leakage should occur by the 'valve 25 in its closed position. In the sec The heat waste is main burner, suflicient gas might be passed 65 goes out at the burner 8. The draft, which i into such burner to cause flash-lighting in the burner, which it is one of the objects of my invention to prevent. The amount of gas is so small that it can be readily taken care of in the pilot burner, and the main burner is always clean and ready to take care of the full flow of gas when the main valve opens, which occurs every time the thermostatic valve opens to exhaust the ac cumulated pressure in the upper compartment of the diaphragm chamber.

The provision of the escapement flange or cup 21, constitutes another important feature of my invention, slnce the escape opening 22 may be made so small as to prevent crowding of the pilot burner while the valve 25 is open. It also enables the open ing 20 to be made much larger than would otherwise be possible; and since the accu.

mulation of suflicient pressure above the diaphragm is essential to the closing of the valve- 19, it will be obvious that the larger this opening 20 is, the quicker this accumulation of pressure can be established. Without the provision of the escapement cu 21 and-its escape opening, all the gas W ich passed through the opening 20 would, of course, pass through. the valve 25 and back to the pilot light.

Owing to the fact that at each full openin of the diaphragm valve, the diaphragm is eld tight' against the periphery of the escapement cup, compelling the escapement'to pass through the small orifice 22 (which,

being of so small an area that the amount of gas passing through it and to the pilot mixer, is hardly perceptible), the pre onderence of pressure on the under side 0 the diaphragm is always maintained as long as the valve 25 is open. This insures the full area for the pipeage of gas to the main burner 9. During the transition from open to closing, or vice versa, the larger amount of gas passing through the hole 20 is allowed to pass through the valve 25 to the pilot light,- thereby increasing its strength or flame at the critical moment, when the puff or otherwise explosion that is always resent at the ignitlon or extinguishing o the flame in any form of gas burner occurs. This is but momentary, and the larger amount of gas does not become wasted but is utilized to help as it were the diaphragm past its center. Instead of carrying the return connection for the escapement gas into the mixer of the pilot light, it may be otherwise arranged to discharge its gas at a point where it will be consumed by said light. It will be noted that this return connection, as shown, discharges into the mixer of the pilot light burner at a point above the openings therein for the admission-of air. The discharge of gas from said pipe is therefore practically to the atmosphere. This is an important feature of my invention, since if the discharge sh uld be mto the pilot lig t supply pipe at a point where there is any- -nection which would interfere with the proper operation of the main valve. The 68- cape pressure front the pressure-closing side of the diaphragm chamber is relatively low and a slight back pressure in the escape pipe is sufiicient to effect the operation of the diaphragm and render it much less sensitive to quick action.

It will be obvious that my invention is susceptible of many changes within the scope of the appended'claims. Thus, it is applicable to heaters of various forms; the details of the valves may be widely changed; and various forms of thermostatlc elements may be employed, and other changes made.

While I have shown and described my invention as applied to a water heater, it will be obvious that it is equally applicable to other forms of heaters andv to the heating of a medium other than water.

What I claim is a 1. In an automatic heating apparatus, the combination of a pilot burner, having an an mixing chamber, a mainburner, an automatic gas valve havin a chamber provided with supply and disc arge connections, a diaphragm in said chamber, a valve member carried by said diaphragm and adapted to control the gas-supply to said main burner, such valve member being exposed to the gas supply pressure tending to unseat the same, said diaphragm being provided with a leak age port for building an opposing gas pressure at the opposite side of the diaphragm,

an escape conduit leading from said oppo- 7 site side ofthe diaphragm and discharging into said pilot burner at a point beyond the air-mixing chamber, and thermostatic means influenced by the heated medium and adapted to control the passage through said escape conduit, whereby said valve member is quickly opened and closed by gas pressure in response to temperature changes in the 2. In an automatic heating apparatus, the combination of a pilot burner, having an air mixing chamber, a main burner, an automatic gas valve having a chamber provided with supply and discharge connections, a diaphragm in said chamber, a gravity-seated valve member carried by said diaphragm and adapted to control the gas-supply to said main burner, said valve member being exposed to the gas supply pressure tending to unseat the same, said diaphragm being provided witha leakage port for building an opposing gas pressure at the opposite side of the diaphragm, an escape conduit leading from said opposite side of the diaphragm and discharging into said pilot burner at a point beyond the air-mixing chambe and thermostatic means influenced heated medium; substantially as described. a

by the heated medium and adapted to control the passage through saidescape conduit, whereby said valve member is quickly opened and closed by gas-pressures in response to temperature changes in the heated medium; substantially as described.

. 3. In an automatic heating apparatus, the combination of a main burner, a pilot burner, an automatic gas valve having a chamber provided. with supply and discharge connections, a diaphragm in said chamber, a gravity-seated valve member on the diaphragm and adapted to control the gas supply to the main burner, saidvalve member being exposed to the gas supply pressure tending to unseat the same, a gas passage communicating with the supply connection and with t e portion of the chamber at the opposite si e of the diaphragm, for building an opposing gas pressure at the opposite side of the diaphragm, a gas escape passage leading; from this portion of the chamber to the pilot burner beyond the air mixing chamber. of said pilot burner, and thermostatic means influenced by the heated medium and adapted to control the passage through said escape conduit, whereby said valve is quickly opened and closed by gas pressure in response'to temperature changes in the heated medium; substantially as described.

4. In an automatic heating apparatus the combination of a main burner, a pilot burner, ,an automatic gas valve having a chamber provided with supply and discharge connections for the main burner; a diaphragm in said chamber, a 'valve member on the diaphragm adapted to control the gas-supply to said main burner, saidvalve member being exposed to the gas supply pressure tending to unseat the same, a leakage passage connecting the two portions of the said chamber at opposite sides of the diaphragm for building an opposing gas pressure at the side of the diaphragm opposite the gas supply pressure, an escape conduitleading from said opposite side to the pilot burner, thermostatic means in-- fiuenced bythe heated medium' and adapted to control the passage through said escape conduit whereby said valve member is quickly opened and closed by gas pressures in response to temperature changes inthe heated medium, and another constantly open source of gas supply for the pilot burner and which is'independent of the supply provided by said escape conduit; substantially as described,

5. In an automatic heating apparatus, the combination of a main burner, a pilot burner, an automatic gas valvehaving a chamber provided wit-h supply and discharge connections for the main burner, a

diaphragm in said chamber, a valve member on the diaphragm adapted to control the gas supply to said mainburner, said valve member being exposed to the gas supply pressure tending to unseat the same, said diaphragm having a leakage port for building an. opposing gas-pressure at the opposite side of the diaphragm, said chamber having at the last named sideof the diaphragm a subsidiary chamber which is arranged to be closed by the diaphragm when the valve is in its full open position, and the subsidiary chamber having a smaller leakage opening into the main chamber, a gas escape conduit leading to the pilot burner from said opposite side of the diaphragm, and means for controlling the passage through said escape conduit to thereby control the opposing pressure on the diaphragm; substantially as described;

6. In an automatic heating apparatus, the combination ,of .a main burner, a pilot burner, an automatic gas valve having a chamber provided with supply and discharge connections for the main burner, a diaphragm in said chamber, a valve member on the diaphragm adapted to control the gas supply to said main burner, said valve .member being exposed to the gas supply pressure tending to unseat the same, said diaphragm having a leakage port for building an opposing gas pressure at the opposite side of the diaphragm, said chamber having at the last named side of the diaphragm a gas escape conduit leading to the pilot burner, means for reducing the flow of gas through the leakage port when the said valve is full-open, and means for controlling the passage through said escape conduit to thereby control the opposing pressure on the diaphragm; substantially as described.

7. In apparatus of the character described, having a main burner and a pilot burner, a valve for cont-rolling the fuel supply to the main burner, a diaphragm chamber, a diaphragm for controlling the action of the said valve, the diaphragm having an escape opening leading to the opposite side thereof, and an escape connection leading from said opposite side of the diaphragm to the pilot burner and discharging to the latter at a point beyond that at which the normal gas supply for the pilot burner is mixed with air, whereby such discharge is free from back pressure, and means for controlling the said escape connection, substantially as described.

In testimony whereof, I have hereunto set my hand.

FREDERICK W. ROBERTSHAW.

lVitnesses JESSE B. HELLER, H; M. CORWIN. 

